US2185568A - Method of shaping air filled rubber to form cushion grips for steering wheels - Google Patents

Description

Jan. 2, 1940. M. B. RATNER METHOD OF SHAPING AI R LLED RUBBER TO FORM CUSHION G S F0 TEERING WHEELS Fi March 6, 1936 '2 Sheets-Sheet 1 NOB/W5 8. RA TA/E/f Jan. 2, 1940. RATNER 7 2,185,568

METHOD OF SHAPING AIR FILLED RUBBER TO FORM CUSHION GRIPS FOR STEERING WHEELS Filed larch 6, 1936 2 Sheets-Sheet 2 MORRIS 8. RH T/VER I D I Patented Jan. 2, 1940 UNITED STATES 2,185,568 7 Y METHOD OF SHAPING AIR. FILLED RUBBER TOFORM CUSHION ING WHEELS.

GRIPS FOR STEER- Morris B. Ratner, Phoenix, Ariz. Application March 6, 1936, Serial 1%.:67544 1 Claim; (01. 18 59) This invention relates to a method of shaping air filled rubber and forming tubular structures thereof capable of being used as a grip for a steering wheel of an automobile or as a grip for other articlesfor which-it may be designed, the grip being so formed that when it is'in use it will fit snugly about the article to which it is applied in close fittingengagement' therewith.

At the present time grips for entirely enclosing the rim of a steering wheel or similar articles, areprovided, but they are made of rubber such as is'used for making tires and'while they are 7 effective toa certain extent in preventing slipping and making driving easier, they have not proved 1 satisfactory. This is particularly true when used upon the steering wheel of an automobile being driven at'high speed, the hands of the driver being practically in direct contact with the rim of the wheel except for the intervening layer of compact rubber, and vibrations will be transmitted to the hands and arms of the'drivezy'and other portions of the body will be affected by the vibrations passing through his arms; The driver has a tendency to grip the wheel and this will cause muscle strain and nervous reactions resulting in the driverbecoming very tired after continuing driving at high speed for a considerable length of .time.

It has been found'that ordinary. rubber heats and sweats the hands and fades to the hand, due to the excessive perspiration caused, and it is not as durable as air filled or sponge rubber.

Attempts have been. 'made to form grips of air filled rubber known as sponge rubber but have not been successful except when made of .short flat strips intended to be secured about the wheel ri'mat points where thewheel is usually grasped andsuch grips have notbeen found satisfactory as a persons hands will move off the grips when making a turn and it is necessary to maintain the hands in substantially a stationary position upon the wheel rim. This is inconvenient and tiring to the driver.

Failure to make a success of forming a grip of sponge rubber which is adapted to entirely enwhen forming the improved grip for a steering the core;

configuration to fit snugly about a steering wheel rim.

Therefore, an object of this invention is thedevelopment ofv a-method whereby aggripi adapted to extend, about and entirely enclose the rim of a steering wheel maybe successively formed of sponge rubber and fit properly thereon when inuse.

Anotherobject of the invention'is to providea method of forming sponge rubber according to '1 which thestock willbe so disposed about a core in amold that as it expands when subjected to heat it will remain in'close contact with the core and the grip when made will fit snugly about the article to'which it is applied."

Another :object .of the invention is to. produce a process of shaping air filled rubber whereby the I grip maybe made as an article to be sold as an accessory or formed directly about the rim' of a wheel, the wheel rim serving as a core during the making of the grip.

The invention isillustrated in the accompany- I ing drawings wherein: Y t Figure 1 is a sectional view of a mold used 5 wheel rim;

Figure 2 is a 'top plan View of the lower mold section with the core in place;

Figure 3 is a view similar to Figure 3 showing the rubber stock applied about the core;

Figure 4 is-a view similar to Figure 1 but showing the mold closed and the rubber stock about Figure 5 is a view similar to Figure 4 showing the stock expanded about the core and filling the mold;"

Figure 6 is an enlarged fragmentary sectional view of the mold;

Figure .7 is a sectional view of a modified meth- 0d wherein a wheel of metal or hard rubber is placed inythe mold as a core and the grip formed directly about therim of the wheel; g Figure 8 is a View taken. along the line 88 of- Figure 'I'with a portion of the stock broken away; Figure 9 is a sectional'view of a second mold into which the wheel and applied rubber are transferred after being removed from the mold shown in Figure 7;

- Figure 10 is an enlarged fragmentary view of Figure 9 showing the rubber expanded and filling Figure 11 is atop plan viewof a steering wheel havingqawooden; metal or composition rim to 5 which a grip has been applied in accordance with another embodiment of this invention;

Figure 12 is a sectional view taken along the line iZ-IZ of Figure 11;

Figure 13 is a fragmentary sectional view illustrating the manner in which the grip shown in Figures 11 and 12 is molded about the metal or composition rim of the steering wheel; and

Figure 14 is a transverse sectional View through the grip portion showing a modified form wherein the air-filled or sponge rubber cushioning member is covered by a thin sheet or layer of smooth or mechanical rubber.

According to the improved method of forming a steering wheel grip or the like of sponge rubber, a mold is provided conforming to the configuration of the grip to be manufactured and in I the present illustration a mold has been shown of theproper outline to form a grip for the steering wheel of an automobile. This mold has upper and lower sections l and 2 formed of duralumin, steel, or other suitable metal. The two mold sections are of solid formation as shown in Figure 1, but havetheir inner faces recessed, as shown at 3 and 4, to provide a chamber 5 when the two sections are in engagement with each other and the recess 3 of the upper section registering with the recess of the lower section, as shown in Figure 4'. The core 6 which may be formed of aluminum, iron, steel, or other suitable materiaL-is formedwith or carried by a plate l, and the plate and core are of such dimensions that when the core is set in place, with the plate resting upon the central portion El of the lower mold section, the core will extend centrally of the recess 4 and axially of'the chamber 5. It should also be noted that the plate I isof such thickness that when the two mold sections are in engagement with each other, the plate will :be engaged between the central portions of the two sections and firmly heldin its proper place to maintain the core axially of the chamber 5.

Previously it has been found impossible to control expansion of the stock from which sponge rubber is made and cause it to move in the proper direction and form a hollow annular grip of the proper dimensions and configuration. The stock is of a consistency similar to dough from which bread is made, and according to this improved method the stock is cut to form stripsof. the proper length and width. One of these strips of stock'is applied to the core, as shown at 51,.and is folded so that it extends about the core in enclosing relation thereto with its margins bearing against, upper and lower faces of the core plate I, as'shown in Figure 4. It is necessary to maintain the stock in close contact with the core during expansion and curing of the stock and in order to do so there have been provided pins 50- which project radially from the core under the plate l and are diagonally disposed at a converging angle. These pins are embedded in the marginal portion of the stock extending about the under portion of the core and they serve very effectively to hold the stock in close contacting engagement with the core. Instead of pins, rings may be provided in the mold to hold the stock about the core, or the core may be formed of twisted metal. After the stock has been applied to the core and the core set-in place upon the lower mold section, the upper mold section is applied to the lower mold section where it is secured in any desired manner. The mold is then subjected to heat and pressure of about three hundred pounds, and as the heat strikes carbon dioxspokes take the place of the core plate 1-. rim l3 which serves as a core is of approximately the diameter of the core 1 and will be centered ide in the stock it expands and convertsthe stock into a spongy mass having a large number of small cells therein. The carbon dioxide gas does not es-i cape from the mold but where it strikes walls of the mold sections, it forms a skin with small depressions or pockets in the surface of the expanded stock and when the stock is fully cured, the grip H will have a pitted surface which has a soft feel when grasped in a persons hand and will not be liable to slip as the pits serve as vacuum cups and create a suction resisting sliding of the grip through the hands of a person holding a steering wheel to which the improved grip has 1 been applied. As the stock is held about the annular core by the pins Iii it will remain in close 1 I contacting engagement with the core and adjacent portions of the core plate and when fully cured will accurately conform to the contour of the core. Therefore, when the mold sections are separated and the core and formedgri'p' removed therefrom, the grip will be of such size and con to each other and the grip will be securely held in place about'the rim of the wheel. By providing ribs upon the walls ofthe chamber 5; the

figuration that. it will fit snugly about the rim of grip may be formed with-ridges similar to thoseupon the tread of a bicycletire and may serve to assist in preventing the grip from slipping through a persons hand. P

It has also. been found that the grip may be directly applied to the rim of a steering wheel and a method of carrying out thisv embodiment of. the invention has been illustrated in Figures 7 through 13. The steering wheel l2, shown in Figures 7 through 10, is formed of metal 'or hard rubber and when such a wheel is used its hub and The in thechamber Id of a shaping mold 5. The

shaping mold is formed of upper and lower. sections which are separable inorder that the steering wheel may be secured between them after the stock Hi has been folded about its rim and the inner portion of the lower mold section has recesses l'l formed radially in its upperface to receive spokes of the wheel. Thereforethe mold sections may have face to face contact'with' 'each. other and the mold be tightlyclosed. After-the 1 mold has been closed it is subjected to suflicient pressure to set the stock about the rim and the mold sections then taken apart and the wheel with the stock adhering thereto removed and transferred to a finishing mold is having a cham- 1 her IQ of approximately the diameter of the chamber 5-and of appreciably greater diameter than the covered rim, as shown clearly in Fi'gure 9. Sections of the mold iii are secured when the wheel is in place and the mold then subjected to heat which expands the stock to fill thecha'my 2,185,568 her or composition rim 22, the surface of, the

rim should be roughened, as indicated at 23, so

' that the stock will adhere. to it. The stock 24 is applied about the rim, as previously set forth, and the covered rim first supported between sections of a forming mold and then transferred to a finishing mold 25in which the stock expands to fill themold chamber and forma grip 26 of the desired size, or the Wheel having its rim' covered with stock may be initially placed inthe mold 25 and the expanding and curing of the stock completed in one operation.

Under the process just described, the spokes of the steering wheel may also be cushioned, as well as the rim if desired, without departing from the spirit of the invention. -A replaceable unit for' the rubber portion of such grips may also be made as described. Such replaceable units when made, are preferably made over the same size as the desired rim,- only a mould lubricant is used on the metal base so as to facilitate If. made under the last described process, the cushion is split on the inner centerwhich permits its rethe removal of the finished product.

moval fromthe cushion from the metal core.

' of soft sponge rubber for a steering wheel rim Should it be desired the sponge rubber stock comprising applying a strip'of sponge rubber stock about'the rim of 'a wheelior the entire circumference'thereof, applying the wheel to a mold having an annular chamber with the rim centered in the chamber, subjecting the mold to pressure to evenly distribute the stock and completely fill the mold and shape the stock about the rim, transferring the wheel to a second mold having a chamber of. greater diameter thanthe chamber of the first mold and disposing the covered rim in centered relation-to the mold chamber, and subjecting the second mold to .heat to expand the stock to completely'fill its chamher and cure the expanded stock to form a soft sponge rubber grip extending entirely about and enclosing the rim.

. MORRIS B. RA'INER.

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